| Message ID | 20220418145945.38797-28-casey@schaufler-ca.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Paul Moore |
| Headers | show |
| Series | [v35,01/29] integrity: disassociate ima_filter_rule from security_audit_rule | expand |
On Mon, Apr 18, 2022 at 11:14 AM Casey Schaufler <casey@schaufler-ca.com> wrote: > > Create a new audit record AUDIT_MAC_OBJ_CONTEXTS. > An example of the MAC_OBJ_CONTEXTS (1421) record is: > > type=MAC_OBJ_CONTEXTS[1421] > msg=audit(1601152467.009:1050): > obj_selinux=unconfined_u:object_r:user_home_t:s0 > > When an audit event includes a AUDIT_MAC_OBJ_CONTEXTS record > the "obj=" field in other records in the event will be "obj=?". > An AUDIT_MAC_OBJ_CONTEXTS record is supplied when the system has > multiple security modules that may make access decisions based > on an object security context. > > Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> > --- > include/linux/audit.h | 5 +++ > include/uapi/linux/audit.h | 1 + > kernel/audit.c | 47 +++++++++++++++++++++++ > kernel/auditsc.c | 79 ++++++++++++-------------------------- > 4 files changed, 77 insertions(+), 55 deletions(-) Acked-by: Paul Moore <paul@paul-moore.com>
On 4/18/22 07:59, Casey Schaufler wrote: > Create a new audit record AUDIT_MAC_OBJ_CONTEXTS. > An example of the MAC_OBJ_CONTEXTS (1421) record is: > > type=MAC_OBJ_CONTEXTS[1421] > msg=audit(1601152467.009:1050): > obj_selinux=unconfined_u:object_r:user_home_t:s0 > > When an audit event includes a AUDIT_MAC_OBJ_CONTEXTS record > the "obj=" field in other records in the event will be "obj=?". > An AUDIT_MAC_OBJ_CONTEXTS record is supplied when the system has > multiple security modules that may make access decisions based > on an object security context. > > Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> > --- > include/linux/audit.h | 5 +++ > include/uapi/linux/audit.h | 1 + > kernel/audit.c | 47 +++++++++++++++++++++++ > kernel/auditsc.c | 79 ++++++++++++-------------------------- > 4 files changed, 77 insertions(+), 55 deletions(-) > > diff --git a/include/linux/audit.h b/include/linux/audit.h > index 14849d5f84b4..1b05eb2dbe77 100644 > --- a/include/linux/audit.h > +++ b/include/linux/audit.h > @@ -191,6 +191,8 @@ extern void audit_log_path_denied(int type, > const char *operation); > extern void audit_log_lost(const char *message); > > +extern void audit_log_object_context(struct audit_buffer *ab, > + struct lsmblob *blob); > extern int audit_log_task_context(struct audit_buffer *ab); > extern void audit_log_task_info(struct audit_buffer *ab); > > @@ -251,6 +253,9 @@ static inline void audit_log_key(struct audit_buffer *ab, char *key) > { } > static inline void audit_log_path_denied(int type, const char *operation) > { } > +static inline void audit_log_object_context(struct audit_buffer *ab, > + struct lsmblob *blob) > +{ } > static inline int audit_log_task_context(struct audit_buffer *ab) > { > return 0; > diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h > index af0aaccfaf57..d25d76b29e3c 100644 > --- a/include/uapi/linux/audit.h > +++ b/include/uapi/linux/audit.h > @@ -144,6 +144,7 @@ > #define AUDIT_MAC_CALIPSO_ADD 1418 /* NetLabel: add CALIPSO DOI entry */ > #define AUDIT_MAC_CALIPSO_DEL 1419 /* NetLabel: del CALIPSO DOI entry */ > #define AUDIT_MAC_TASK_CONTEXTS 1420 /* Multiple LSM task contexts */ > +#define AUDIT_MAC_OBJ_CONTEXTS 1421 /* Multiple LSM objext contexts */ > > #define AUDIT_FIRST_KERN_ANOM_MSG 1700 > #define AUDIT_LAST_KERN_ANOM_MSG 1799 > diff --git a/kernel/audit.c b/kernel/audit.c > index 8ed2d717c217..a8c3ec6ba60b 100644 > --- a/kernel/audit.c > +++ b/kernel/audit.c > @@ -2226,6 +2226,53 @@ static void audit_buffer_aux_end(struct audit_buffer *ab) > ab->skb = skb_peek(&ab->skb_list); > } > > +void audit_log_object_context(struct audit_buffer *ab, struct lsmblob *blob) > +{ > + int i; > + int error; > + struct lsmcontext context; > + > + if (!lsm_multiple_contexts()) { > + error = security_secid_to_secctx(blob, &context, LSMBLOB_FIRST); > + if (error) { > + if (error != -EINVAL) > + goto error_path; > + return; > + } > + audit_log_format(ab, " obj=%s", context.context); > + security_release_secctx(&context); > + } else { > + audit_log_format(ab, " obj=?"); > + error = audit_buffer_aux_new(ab, AUDIT_MAC_OBJ_CONTEXTS); > + if (error) > + goto error_path; > + > + for (i = 0; i < LSMBLOB_ENTRIES; i++) { > + if (blob->secid[i] == 0) > + continue; > + error = security_secid_to_secctx(blob, &context, i); > + if (error) { > + audit_log_format(ab, "%sobj_%s=?", > + i ? " " : "", > + lsm_slot_to_name(i)); > + if (error != -EINVAL) > + audit_panic("error in audit_log_object_context"); > + } else { > + audit_log_format(ab, "%sobj_%s=%s", > + i ? " " : "", > + lsm_slot_to_name(i), > + context.context); > + security_release_secctx(&context); > + } > + } > + > + audit_buffer_aux_end(ab); > + } > + return; > + > +error_path: > + audit_panic("error in audit_log_object_context"); This moves the audit_panic around, so certain operations are not done before the call. I am currently not sure of the implications. Paul? > +} > > int audit_log_task_context(struct audit_buffer *ab) > { > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > index 557713954a69..04bf3c04ef3d 100644 > --- a/kernel/auditsc.c > +++ b/kernel/auditsc.c > @@ -1114,36 +1114,25 @@ static inline void audit_free_context(struct audit_context *context) > kfree(context); > } > > -static int audit_log_pid_context(struct audit_context *context, pid_t pid, > - kuid_t auid, kuid_t uid, > - unsigned int sessionid, > - struct lsmblob *blob, char *comm) > +static void audit_log_pid_context(struct audit_context *context, pid_t pid, > + kuid_t auid, kuid_t uid, > + unsigned int sessionid, > + struct lsmblob *blob, char *comm) > { > struct audit_buffer *ab; > - struct lsmcontext lsmctx; > - int rc = 0; > > ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); > if (!ab) > - return rc; > + return; > > audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, > from_kuid(&init_user_ns, auid), > from_kuid(&init_user_ns, uid), sessionid); > - if (lsmblob_is_set(blob)) { > - if (security_secid_to_secctx(blob, &lsmctx, LSMBLOB_FIRST)) { > - audit_log_format(ab, " obj=(none)"); > - rc = 1; > - } else { > - audit_log_format(ab, " obj=%s", lsmctx.context); > - security_release_secctx(&lsmctx); > - } > - } > + if (lsmblob_is_set(blob)) > + audit_log_object_context(ab, blob); > audit_log_format(ab, " ocomm="); > audit_log_untrustedstring(ab, comm); > audit_log_end(ab); > - > - return rc; > } > > static void audit_log_execve_info(struct audit_context *context, > @@ -1420,18 +1409,10 @@ static void show_special(struct audit_context *context, int *call_panic) If pushing audit_panic into audit_log_object_context() is acceptable then this call_panic arg is no longer needed. The same goes for the call_panic arg in audit_log_name(). And call_panic can be dropped from audit_log_exit() > from_kgid(&init_user_ns, context->ipc.gid), > context->ipc.mode); > if (osid) { > - struct lsmcontext lsmcxt; > struct lsmblob blob; > > lsmblob_init(&blob, osid); > - if (security_secid_to_secctx(&blob, &lsmcxt, > - LSMBLOB_FIRST)) { > - audit_log_format(ab, " osid=%u", osid); > - *call_panic = 1; > - } else { > - audit_log_format(ab, " obj=%s", lsmcxt.context); > - security_release_secctx(&lsmcxt); > - } > + audit_log_object_context(ab, &blob); > } > if (context->ipc.has_perm) { > audit_log_end(ab); > @@ -1588,19 +1569,8 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n, > from_kgid(&init_user_ns, n->gid), > MAJOR(n->rdev), > MINOR(n->rdev)); > - if (lsmblob_is_set(&n->lsmblob)) { > - struct lsmcontext lsmctx; > - > - if (security_secid_to_secctx(&n->lsmblob, &lsmctx, > - LSMBLOB_FIRST)) { > - audit_log_format(ab, " osid=?"); > - if (call_panic) > - *call_panic = 2; > - } else { > - audit_log_format(ab, " obj=%s", lsmctx.context); > - security_release_secctx(&lsmctx); > - } > - } > + if (lsmblob_is_set(&n->lsmblob)) > + audit_log_object_context(ab, &n->lsmblob); > > /* log the audit_names record type */ > switch (n->type) { > @@ -1805,21 +1775,20 @@ static void audit_log_exit(void) > struct audit_aux_data_pids *axs = (void *)aux; > > for (i = 0; i < axs->pid_count; i++) > - if (audit_log_pid_context(context, axs->target_pid[i], > - axs->target_auid[i], > - axs->target_uid[i], > - axs->target_sessionid[i], > - &axs->target_lsm[i], > - axs->target_comm[i])) > - call_panic = 1; > - } > - > - if (context->target_pid && > - audit_log_pid_context(context, context->target_pid, > - context->target_auid, context->target_uid, > - context->target_sessionid, > - &context->target_lsm, context->target_comm)) > - call_panic = 1; > + audit_log_pid_context(context, axs->target_pid[i], > + axs->target_auid[i], > + axs->target_uid[i], > + axs->target_sessionid[i], > + &axs->target_lsm[i], > + axs->target_comm[i]); > + } > + > + if (context->target_pid) > + audit_log_pid_context(context, context->target_pid, > + context->target_auid, context->target_uid, > + context->target_sessionid, > + &context->target_lsm, > + context->target_comm); > > if (context->pwd.dentry && context->pwd.mnt) { > ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
On Mon, Apr 25, 2022 at 11:38 PM John Johansen <john.johansen@canonical.com> wrote: > On 4/18/22 07:59, Casey Schaufler wrote: > > Create a new audit record AUDIT_MAC_OBJ_CONTEXTS. > > An example of the MAC_OBJ_CONTEXTS (1421) record is: > > > > type=MAC_OBJ_CONTEXTS[1421] > > msg=audit(1601152467.009:1050): > > obj_selinux=unconfined_u:object_r:user_home_t:s0 > > > > When an audit event includes a AUDIT_MAC_OBJ_CONTEXTS record > > the "obj=" field in other records in the event will be "obj=?". > > An AUDIT_MAC_OBJ_CONTEXTS record is supplied when the system has > > multiple security modules that may make access decisions based > > on an object security context. > > > > Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> > > --- > > include/linux/audit.h | 5 +++ > > include/uapi/linux/audit.h | 1 + > > kernel/audit.c | 47 +++++++++++++++++++++++ > > kernel/auditsc.c | 79 ++++++++++++-------------------------- > > 4 files changed, 77 insertions(+), 55 deletions(-) ... > > diff --git a/kernel/audit.c b/kernel/audit.c > > index 8ed2d717c217..a8c3ec6ba60b 100644 > > --- a/kernel/audit.c > > +++ b/kernel/audit.c > > @@ -2226,6 +2226,53 @@ static void audit_buffer_aux_end(struct audit_buffer *ab) > > ab->skb = skb_peek(&ab->skb_list); > > } > > > > +void audit_log_object_context(struct audit_buffer *ab, struct lsmblob *blob) > > +{ > > + int i; > > + int error; > > + struct lsmcontext context; > > + > > + if (!lsm_multiple_contexts()) { > > + error = security_secid_to_secctx(blob, &context, LSMBLOB_FIRST); > > + if (error) { > > + if (error != -EINVAL) > > + goto error_path; > > + return; > > + } > > + audit_log_format(ab, " obj=%s", context.context); > > + security_release_secctx(&context); > > + } else { > > + audit_log_format(ab, " obj=?"); > > + error = audit_buffer_aux_new(ab, AUDIT_MAC_OBJ_CONTEXTS); > > + if (error) > > + goto error_path; > > + > > + for (i = 0; i < LSMBLOB_ENTRIES; i++) { > > + if (blob->secid[i] == 0) > > + continue; > > + error = security_secid_to_secctx(blob, &context, i); > > + if (error) { > > + audit_log_format(ab, "%sobj_%s=?", > > + i ? " " : "", > > + lsm_slot_to_name(i)); > > + if (error != -EINVAL) > > + audit_panic("error in audit_log_object_context"); > > + } else { > > + audit_log_format(ab, "%sobj_%s=%s", > > + i ? " " : "", > > + lsm_slot_to_name(i), > > + context.context); > > + security_release_secctx(&context); > > + } > > + } > > + > > + audit_buffer_aux_end(ab); > > + } > > + return; > > + > > +error_path: > > + audit_panic("error in audit_log_object_context"); > > This moves the audit_panic around, so certain operations are not > done before the call. I am currently not sure of the implications. Short version: It's okay. Longer version: The audit_panic() call is either going to panic the kernel (NOT the default), do a pr_err(), or essentially be a no-op. In the case of the full blown kernel panic we don't really care, the system is going to die before there is any chance of this record in progress getting logged. In the case of a pr_err() or no-op the key part is making sure we leave the audit_buffer in a consistent state so that we preserve whatever information is already present. In the !lsm_multiple_contexts case we simply return without making any changes to the audit_buffer so we're good there; in the multiple LSM case we always end the aux record properly (using a "?" when necessary) if an aux record has been successfully created. Feel free to point out a specific scenario that you think looks wrong - I may have missed it - but I believe this code to be correct. > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > > index 557713954a69..04bf3c04ef3d 100644 > > --- a/kernel/auditsc.c > > +++ b/kernel/auditsc.c > > @@ -1420,18 +1409,10 @@ static void show_special(struct audit_context *context, int *call_panic) > > If pushing audit_panic into audit_log_object_context() is acceptable then this call_panic arg is > no longer needed. The same goes for the call_panic arg in audit_log_name(). And call_panic can > be dropped from audit_log_exit() Good catch. I suspect this is a vestige from when audit_log_end() used to do the record's skb write to userspace, meaning it was possible that you might get some of the records written to userspace before the system killed itself. Now with all of the queuing involved it's less likely that this would be the case, and even if it does happen in some cases, it's basically a toss up depending on how the system is loaded, the scheduler, etc.
On 4/26/22 11:57, Paul Moore wrote: > On Mon, Apr 25, 2022 at 11:38 PM John Johansen > <john.johansen@canonical.com> wrote: >> On 4/18/22 07:59, Casey Schaufler wrote: >>> Create a new audit record AUDIT_MAC_OBJ_CONTEXTS. >>> An example of the MAC_OBJ_CONTEXTS (1421) record is: >>> >>> type=MAC_OBJ_CONTEXTS[1421] >>> msg=audit(1601152467.009:1050): >>> obj_selinux=unconfined_u:object_r:user_home_t:s0 >>> >>> When an audit event includes a AUDIT_MAC_OBJ_CONTEXTS record >>> the "obj=" field in other records in the event will be "obj=?". >>> An AUDIT_MAC_OBJ_CONTEXTS record is supplied when the system has >>> multiple security modules that may make access decisions based >>> on an object security context. >>> >>> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> >>> --- >>> include/linux/audit.h | 5 +++ >>> include/uapi/linux/audit.h | 1 + >>> kernel/audit.c | 47 +++++++++++++++++++++++ >>> kernel/auditsc.c | 79 ++++++++++++-------------------------- >>> 4 files changed, 77 insertions(+), 55 deletions(-) > > ... > >>> diff --git a/kernel/audit.c b/kernel/audit.c >>> index 8ed2d717c217..a8c3ec6ba60b 100644 >>> --- a/kernel/audit.c >>> +++ b/kernel/audit.c >>> @@ -2226,6 +2226,53 @@ static void audit_buffer_aux_end(struct audit_buffer *ab) >>> ab->skb = skb_peek(&ab->skb_list); >>> } >>> >>> +void audit_log_object_context(struct audit_buffer *ab, struct lsmblob *blob) >>> +{ >>> + int i; >>> + int error; >>> + struct lsmcontext context; >>> + >>> + if (!lsm_multiple_contexts()) { >>> + error = security_secid_to_secctx(blob, &context, LSMBLOB_FIRST); >>> + if (error) { >>> + if (error != -EINVAL) >>> + goto error_path; >>> + return; >>> + } >>> + audit_log_format(ab, " obj=%s", context.context); >>> + security_release_secctx(&context); >>> + } else { >>> + audit_log_format(ab, " obj=?"); >>> + error = audit_buffer_aux_new(ab, AUDIT_MAC_OBJ_CONTEXTS); >>> + if (error) >>> + goto error_path; >>> + >>> + for (i = 0; i < LSMBLOB_ENTRIES; i++) { >>> + if (blob->secid[i] == 0) >>> + continue; >>> + error = security_secid_to_secctx(blob, &context, i); >>> + if (error) { >>> + audit_log_format(ab, "%sobj_%s=?", >>> + i ? " " : "", >>> + lsm_slot_to_name(i)); >>> + if (error != -EINVAL) >>> + audit_panic("error in audit_log_object_context"); >>> + } else { >>> + audit_log_format(ab, "%sobj_%s=%s", >>> + i ? " " : "", >>> + lsm_slot_to_name(i), >>> + context.context); >>> + security_release_secctx(&context); >>> + } >>> + } >>> + >>> + audit_buffer_aux_end(ab); >>> + } >>> + return; >>> + >>> +error_path: >>> + audit_panic("error in audit_log_object_context"); >> >> This moves the audit_panic around, so certain operations are not >> done before the call. I am currently not sure of the implications. > > Short version: It's okay. > > Longer version: The audit_panic() call is either going to panic the > kernel (NOT the default), do a pr_err(), or essentially be a no-op. > In the case of the full blown kernel panic we don't really care, the > system is going to die before there is any chance of this record in > progress getting logged. In the case of a pr_err() or no-op the key > part is making sure we leave the audit_buffer in a consistent state so > that we preserve whatever information is already present. In the > !lsm_multiple_contexts case we simply return without making any > changes to the audit_buffer so we're good there; in the multiple LSM > case we always end the aux record properly (using a "?" when > necessary) if an aux record has been successfully created. > > Feel free to point out a specific scenario that you think looks wrong > - I may have missed it - but I believe this code to be correct. > mostly I am good, I was worried I was missing something since the old code made an effort to have the call of audit_panic() at the end. The current change does result in potential multiple calls to audit_panic() in a single audit_log_exit(). This doesn't matter in the case of a full blown kernel panic, but it could result in multiple pr_err() messages where previously the code would only generate one. It does simplify the code, and the case should be quite rare so I am fine with the trade-off. >>> diff --git a/kernel/auditsc.c b/kernel/auditsc.c >>> index 557713954a69..04bf3c04ef3d 100644 >>> --- a/kernel/auditsc.c >>> +++ b/kernel/auditsc.c >>> @@ -1420,18 +1409,10 @@ static void show_special(struct audit_context *context, int *call_panic) >> >> If pushing audit_panic into audit_log_object_context() is acceptable then this call_panic arg is >> no longer needed. The same goes for the call_panic arg in audit_log_name(). And call_panic can >> be dropped from audit_log_exit() > > Good catch. > > I suspect this is a vestige from when audit_log_end() used to do the > record's skb write to userspace, meaning it was possible that you > might get some of the records written to userspace before the system > killed itself. Now with all of the queuing involved it's less likely > that this would be the case, and even if it does happen in some cases, > it's basically a toss up depending on how the system is loaded, the > scheduler, etc. >
diff --git a/include/linux/audit.h b/include/linux/audit.h index 14849d5f84b4..1b05eb2dbe77 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -191,6 +191,8 @@ extern void audit_log_path_denied(int type, const char *operation); extern void audit_log_lost(const char *message); +extern void audit_log_object_context(struct audit_buffer *ab, + struct lsmblob *blob); extern int audit_log_task_context(struct audit_buffer *ab); extern void audit_log_task_info(struct audit_buffer *ab); @@ -251,6 +253,9 @@ static inline void audit_log_key(struct audit_buffer *ab, char *key) { } static inline void audit_log_path_denied(int type, const char *operation) { } +static inline void audit_log_object_context(struct audit_buffer *ab, + struct lsmblob *blob) +{ } static inline int audit_log_task_context(struct audit_buffer *ab) { return 0; diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h index af0aaccfaf57..d25d76b29e3c 100644 --- a/include/uapi/linux/audit.h +++ b/include/uapi/linux/audit.h @@ -144,6 +144,7 @@ #define AUDIT_MAC_CALIPSO_ADD 1418 /* NetLabel: add CALIPSO DOI entry */ #define AUDIT_MAC_CALIPSO_DEL 1419 /* NetLabel: del CALIPSO DOI entry */ #define AUDIT_MAC_TASK_CONTEXTS 1420 /* Multiple LSM task contexts */ +#define AUDIT_MAC_OBJ_CONTEXTS 1421 /* Multiple LSM objext contexts */ #define AUDIT_FIRST_KERN_ANOM_MSG 1700 #define AUDIT_LAST_KERN_ANOM_MSG 1799 diff --git a/kernel/audit.c b/kernel/audit.c index 8ed2d717c217..a8c3ec6ba60b 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2226,6 +2226,53 @@ static void audit_buffer_aux_end(struct audit_buffer *ab) ab->skb = skb_peek(&ab->skb_list); } +void audit_log_object_context(struct audit_buffer *ab, struct lsmblob *blob) +{ + int i; + int error; + struct lsmcontext context; + + if (!lsm_multiple_contexts()) { + error = security_secid_to_secctx(blob, &context, LSMBLOB_FIRST); + if (error) { + if (error != -EINVAL) + goto error_path; + return; + } + audit_log_format(ab, " obj=%s", context.context); + security_release_secctx(&context); + } else { + audit_log_format(ab, " obj=?"); + error = audit_buffer_aux_new(ab, AUDIT_MAC_OBJ_CONTEXTS); + if (error) + goto error_path; + + for (i = 0; i < LSMBLOB_ENTRIES; i++) { + if (blob->secid[i] == 0) + continue; + error = security_secid_to_secctx(blob, &context, i); + if (error) { + audit_log_format(ab, "%sobj_%s=?", + i ? " " : "", + lsm_slot_to_name(i)); + if (error != -EINVAL) + audit_panic("error in audit_log_object_context"); + } else { + audit_log_format(ab, "%sobj_%s=%s", + i ? " " : "", + lsm_slot_to_name(i), + context.context); + security_release_secctx(&context); + } + } + + audit_buffer_aux_end(ab); + } + return; + +error_path: + audit_panic("error in audit_log_object_context"); +} int audit_log_task_context(struct audit_buffer *ab) { diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 557713954a69..04bf3c04ef3d 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1114,36 +1114,25 @@ static inline void audit_free_context(struct audit_context *context) kfree(context); } -static int audit_log_pid_context(struct audit_context *context, pid_t pid, - kuid_t auid, kuid_t uid, - unsigned int sessionid, - struct lsmblob *blob, char *comm) +static void audit_log_pid_context(struct audit_context *context, pid_t pid, + kuid_t auid, kuid_t uid, + unsigned int sessionid, + struct lsmblob *blob, char *comm) { struct audit_buffer *ab; - struct lsmcontext lsmctx; - int rc = 0; ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); if (!ab) - return rc; + return; audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, from_kuid(&init_user_ns, auid), from_kuid(&init_user_ns, uid), sessionid); - if (lsmblob_is_set(blob)) { - if (security_secid_to_secctx(blob, &lsmctx, LSMBLOB_FIRST)) { - audit_log_format(ab, " obj=(none)"); - rc = 1; - } else { - audit_log_format(ab, " obj=%s", lsmctx.context); - security_release_secctx(&lsmctx); - } - } + if (lsmblob_is_set(blob)) + audit_log_object_context(ab, blob); audit_log_format(ab, " ocomm="); audit_log_untrustedstring(ab, comm); audit_log_end(ab); - - return rc; } static void audit_log_execve_info(struct audit_context *context, @@ -1420,18 +1409,10 @@ static void show_special(struct audit_context *context, int *call_panic) from_kgid(&init_user_ns, context->ipc.gid), context->ipc.mode); if (osid) { - struct lsmcontext lsmcxt; struct lsmblob blob; lsmblob_init(&blob, osid); - if (security_secid_to_secctx(&blob, &lsmcxt, - LSMBLOB_FIRST)) { - audit_log_format(ab, " osid=%u", osid); - *call_panic = 1; - } else { - audit_log_format(ab, " obj=%s", lsmcxt.context); - security_release_secctx(&lsmcxt); - } + audit_log_object_context(ab, &blob); } if (context->ipc.has_perm) { audit_log_end(ab); @@ -1588,19 +1569,8 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n, from_kgid(&init_user_ns, n->gid), MAJOR(n->rdev), MINOR(n->rdev)); - if (lsmblob_is_set(&n->lsmblob)) { - struct lsmcontext lsmctx; - - if (security_secid_to_secctx(&n->lsmblob, &lsmctx, - LSMBLOB_FIRST)) { - audit_log_format(ab, " osid=?"); - if (call_panic) - *call_panic = 2; - } else { - audit_log_format(ab, " obj=%s", lsmctx.context); - security_release_secctx(&lsmctx); - } - } + if (lsmblob_is_set(&n->lsmblob)) + audit_log_object_context(ab, &n->lsmblob); /* log the audit_names record type */ switch (n->type) { @@ -1805,21 +1775,20 @@ static void audit_log_exit(void) struct audit_aux_data_pids *axs = (void *)aux; for (i = 0; i < axs->pid_count; i++) - if (audit_log_pid_context(context, axs->target_pid[i], - axs->target_auid[i], - axs->target_uid[i], - axs->target_sessionid[i], - &axs->target_lsm[i], - axs->target_comm[i])) - call_panic = 1; - } - - if (context->target_pid && - audit_log_pid_context(context, context->target_pid, - context->target_auid, context->target_uid, - context->target_sessionid, - &context->target_lsm, context->target_comm)) - call_panic = 1; + audit_log_pid_context(context, axs->target_pid[i], + axs->target_auid[i], + axs->target_uid[i], + axs->target_sessionid[i], + &axs->target_lsm[i], + axs->target_comm[i]); + } + + if (context->target_pid) + audit_log_pid_context(context, context->target_pid, + context->target_auid, context->target_uid, + context->target_sessionid, + &context->target_lsm, + context->target_comm); if (context->pwd.dentry && context->pwd.mnt) { ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
Create a new audit record AUDIT_MAC_OBJ_CONTEXTS. An example of the MAC_OBJ_CONTEXTS (1421) record is: type=MAC_OBJ_CONTEXTS[1421] msg=audit(1601152467.009:1050): obj_selinux=unconfined_u:object_r:user_home_t:s0 When an audit event includes a AUDIT_MAC_OBJ_CONTEXTS record the "obj=" field in other records in the event will be "obj=?". An AUDIT_MAC_OBJ_CONTEXTS record is supplied when the system has multiple security modules that may make access decisions based on an object security context. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> --- include/linux/audit.h | 5 +++ include/uapi/linux/audit.h | 1 + kernel/audit.c | 47 +++++++++++++++++++++++ kernel/auditsc.c | 79 ++++++++++++-------------------------- 4 files changed, 77 insertions(+), 55 deletions(-)